What is the blue light hazard?
I believe that many parents think of the term "eye protection" when they buy table lamps for their children. The opposite conceptual name is "blue light hazard". Many products on the market are marked with "reduce blue light" and "no blue light". The grades are "superior" and "exempt level". There are many nouns and phrases, and they are very messy. How to distinguish between many people is confused and at a loss. .
The most ideal light source is sunlight, but artificial light sources must be used at night. Everyone knows that visible light has a wavelength of 380-780nm, which contains the common blue light spectrum (400nm-480nm).
White light is formed by a mixture of a variety of monochromatic lights, the most basic of which is red, green and blue. The indicator for measuring the color of white light is color temperature, the unit is K (Kelvin). Generally, the color temperature range of white light for LED lighting is: 2700K-7000K. Increasing the blue component of the white light will increase the color temperature of the white light. If the blue component of the white light is reduced and the red light component will be increased, the color temperature of the white light will decrease.
Photon energy and wavelength
It can be seen from the figure that in the visible light range, blue light (wavelength 400-500nm) photons carry the most energy, which is called high-energy light.
The blue light hazard is mainly a photochemical reaction caused by light radiation rich in high-energy blue light, which leads to the harm of retinal damage. Since the blue light components in LED products are relatively rich, and the brightness of exposed LED light sources is often high, LED lamps may have hidden risks of blue light hazards.
The mechanism of blue light hazard (simplified diagram)
A few days ago, the China Quality Certification Center issued a notice that the latest version of the national mandatory standard GB7000.1-2015 "Lamps Part 1: General Requirements and Tests" will be implemented soon. Starting from January 1, 2017, the center will adopt the new version of the standard to implement certification And issued a new version of the standard certification, no longer issued the old version of the standard certification.
The new version of the standard specifically increases the requirements for blue light hazards
For lamps with integral LEDs or LED modules, blue light hazard assessment should be carried out according to IEC/TR62778.
Blu-ray hazard classification
The standard points out: For children's portable lamps and night lights, the blue light hazard level measured at a distance of 200mm shall not exceed RG1. From the classification of blue light hazard levels, it is recommended that when purchasing lamps, this standard should be at least RG0, and there is a relevant certification report, because the lower the Lb value, the better, and it is not to be underestimated to care for the health of the eyes.
What exactly does blue light harm?
1. High-energy short-wave blue light penetrates the cornea and lens directly to the bottom of the retina, directly causing irreversible chemical damage to the retinal nerve of the eye, directly or indirectly causing damage to the cells in the macular area.
2. Blue light can cause damage to the fundus after cataract surgery
With age, the lens of the human body will gradually become yellowish, which helps to filter blue light and avoid the harm of blue light. However, after cataract surgery, the patient loses these natural barrier "lenses", and blue light will reach the retina directly, and then damage the retinal pigment epithelial cells, seriously affecting the health of the fundus.
3. Blue light can cause blurred vision, cause visual fatigue, and cause VDT (Visual Display Terminals) syndrome
After the blue light enters the fundus and is focused, it falls between the retina and the lens instead of on the retina. This will aggravate chromatic aberration and visual ambiguity, and then the eye muscles will be over tense, the eye blood supply will be over tense, and the eye blood supply will be strengthened. , Thereby increasing fatigue.
4. Blue light can inhibit the secretion of melatonin, destroy the balance of hormone secretion, affect the quality of sleep, and increase the incidence of major diseases.
Love your eyes, protect your eyes, use your eyes scientifically, and bathe your eyes in the sun.
